a = [1]
q = int(input())
for i in range(q):
    b = list(map(int,input().split()))
    b0 = b[0]
    x = int(b[1])
    if b0 == 1:
        index = a.index(x)
        a.insert(index+1,int(b[2]))
    elif b0 == 2:
        index = a.index(x)
        if index == len(a)-1:
            print('0')
        else:
            print(a[index+1])
    elif b0 == 3:
        index = a.index(x)
        a.pop(index+1)